Method for subscription and notification in M2M communication system and apparatus for same

1. A method performed by a Machine-to-Machine (M2M) device in which a first resource and a second resource are configured such that the second resource corresponds to a parent resource of the first resource, the method comprising:

adding first condition information to a filtering attribute of the first resource;

receiving a request message from a first entity, the request message comprising first information indicating an address corresponding to the second resource and second information indicating an operation to be performed by the M2M device; and

when a specific condition is satisfied, sending a notification message to a second entity indicated by address information configured in the first resource,

wherein the specific condition includes the following condition (1):

(1) when the filtering attribute of the first resource comprises the first condition information and the operation accesses the second resource, the operation matches with a value of the first condition information,

wherein the operation corresponds to a retrieval, and

wherein each of the first resource and the second resource represents a data structure which is uniquely addressable using a unique address.

2. The method of claim 1 , wherein the first condition information is used for monitoring whether the operation is attempted irrespective of whether the operation is performed.

3. The method of claim 1 , wherein the operation further corresponds to a creation, an update, or a deletion.

4. The method of claim 1 , wherein the notification message comprises a parameter corresponding to the operation.

5. The method of claim 1 , further comprising:

adding second condition information to the filtering attribute of the first resource,

wherein the specific condition further includes the following condition (2):

(2) when the filtering attribute of the first resource comprises the second condition information, and when the second resource or a child resource of the second resource is changed by the operation, a changed status of the second resource or the child resource of the second resource matches with a value of the second condition information.

6. The method of claim 5 , wherein when the second condition information is added to the filtering attribute of the first resource, the notification message comprises a parameter corresponding to the changed status.

7. The method of claim 1 , wherein the specific condition further includes the following conditions (3) and (4):

(3) the second entity sending the request message has a retrieve permission for the second resource, and

(4) when the first entity and the second entity are different from each other, the first entity has an access right for sending a notification message to the second entity.

8. The method of claim 1 , wherein the first resource corresponds to a resource for a subscription, and the second resource corresponds to a subscription target resource.

9. A Machine-to-Machine (M2M) device in which a first resource and a second resource are configured such that the second resource corresponds to a parent resource of the first resource, the M2M device comprising:

a network interface unit; and

a processor configured to:

add first condition information to a filtering attribute of the first resource,

receive a request message from a first entity, the request message comprising first information indicating an address corresponding to the second resource and second information indicating an operation to be performed by the device, and

when a specific condition is satisfied, send a notification message to a second entity indicated by address information configured in the first resource, wherein the specific condition includes the following condition (1):

(1) when the filtering attribute of the first resource comprises the first condition information and the operation accesses the second resource, the operation matches with a value of the first condition information,

wherein the operation corresponds to retrieval, and

wherein each of the first resource and the second resource represents a data structure which is uniquely addressable using a unique address.

10. The M2M device of claim 8 , wherein the first condition information is used for monitoring whether the operation is attempted irrespective of whether the operation is performed.

11. The M2M device of claim 9 , wherein the operation further corresponds to a creation, an update, or a deletion.

12. The M2M device of claim 9 , wherein the notification message comprises a parameter corresponding to the operation.

13. The M2M device of claim 9 , wherein the processor is further configured to:

add second condition information to the filtering attribute of the first resource,

wherein the specific condition further includes the following condition (2):

(2) when the filtering attribute of the first resource comprises the second condition information, and when the second resource or a child resource of the second resource is changed by the operation, a changed status of the second resource or the child resource of the second resource matches with a value of the second condition information.

14. The M2M device of claim 13 , wherein when the second condition information is added to the filtering attribute of the first resource, the notification message comprises a parameter corresponding to the changed status.

15. The M2M device of claim 9 , wherein the specific condition further includes the following conditions (3) and (4):

(3) the second entity sending the request message has a retrieve permission for the second resource, and

(4) when the first entity and the second entity are different from each other, the first entity has an access right for sending a notification message to the second entity.

16. The M2M device of claim 9 , wherein the first resource corresponds to a resource for a subscription, and the second resource corresponds to a subscription target resource.